Rondeezzee310

thats funny u say that. i had a 86 iroc with a 350 but my plate fram said "I BET YOUR 350 WONT SPANK THIS 305"it works everytime.

1gary

Your still not feeding a 383 c.i.engine properly.Steel stock production heads are only going to give you 170cc intake runners before you run into water.Really not to insist,but a 383 needs atleast a 180cc runner or better.The production Vortec heads are a bad answer in that they give you a increased c/r without a matched intake runner for the size of the engine.They are fine for a 355,but for a 383,they really are not sized correctly.The GM Hi-Po Vortec heads are a different story:

Go to page 176:

http://www.gmpartsdirect.com/performance_parts/2012/

But as I told you before,they do not compare to the aftermarket heads in the way they flow.The idea of CNC porting being advertized can be misleading.Companies that have done their research and have programs to running 5 position porting are the ones who truly do effective porting.The other thing is the cross-section of a measured port and how that is formed is tons more important than the rated cc runner size.My point here is you can and will have two 180 cc runner sets of heads from different companies that will perform entirely different.One much better and the other much.much,worst.

The idea of 5.6 rods in 400's and their use in 383 builds not matter much because they work,is the same thing in a 383 is akin to using a 400 in the first place. Here I mean the only thing your gaining by not building a 400 is with a 383 you don't have to deal with the poor design steam hole cooling of a 400 and you end up having a 383/less c.i. engine being a 400 is bigger.Does it work,well really does it run??. Yep. But don't think that because it just runs and it is,"well just for the street",it doesn't matter much.Got to ask yourself,is that what we are all about??. God I hope not,because that becomes a slipper slope on tons of other things in a build too.Just running and good enough!!.

When I read about him just unplugging the dizzy and not using the sensors,I knew for sure that is where his lost of gas mileage is.Then compounding it with a 305 carb too.Buell you can not do that.Period.Now I am on a full court press to get you to do something about it.That is a huge part of your problem.All the other things all of us have suggested are also a factor in overall performance,but it just doesn't compare in a impact to the dizzy and carb and if you where to change cam,pistons,rods,heads,well everything else and still never change the dizzy and carb,it would still not run right.You NEED TO ADDRESS THAT FIRST!!!.I want to read you bought a vac HEI and carb and those results.

Hell,not that I am trying to sell anything here,but I do have a Vac HEI brand new that was re-curved on a Sun machine by Jan-Cen automotive for full advance at 2500 rpm.It is for the days back when I was running a Bowtie 4.3.In order to use it for a v8 all that needs to be done is to replace the inductor to a v8.It's been in my shop for yrs,so I don't care is it sells or not,but to help you out,I'll sell it for like $50.00 bucks plus shipping.It is a bare dizzy only without a cap,rotor or coil but as I said it is brand new never been in a engine cost me in the lower $200's back then.Send me a PM and I could send you some pictures.

Buell-fix the carb and dizzy from me or anyone else.LOL-Stop dancing with the stars here on all the other things.

DIGGLER

iTrader: (1)

with 9.3:1 and stock heads i would really focus on low end torque. its not gonna breath up top, so it needs to make all its power down low. cam will need to be in the "rv" range. something small. intake needs to be a dual plane, and it needs to have a carb/dizzy that are not computer controlled and will run well on this engine.

one other thought i had was to try and find an unmolested quadrajet off of a 400. mid 70's caprices and trucks would have had that combo. would probably run pretty good on the 383 with a small cam.

1gary

Yep.A carb like that from a pick and pull would likely be pretty cheap.Actually might be a tad bit rich set for a 400.

Savage388

1gary I'm not saying I have the optimal package but I do make great power down low and at least 400 fwhp which is pretty respectable on the street. I also never said that short rods were something you would build and be good enough but they do work fine it's just not a screamer which with my heads doesn't matter.


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buell_13

Yeah I can't believe that I did't think about the ecm.... I just figured carb it's old shcool..... I feel so dumb...... Ok I have swapped dizzys now onto the carb..... I will find one asap. I am interested in what diggler was saying... I can build great low end and run it till I can afford to put badass trick flows on right? I would like to hear about a good low cam that I could run to improve things..... also side note without knowing the cam parameters any best guesses to timing degrees? I have it @ roughly 10 degrees advanced right now.... after warming up it still doesn't like to restart as mentioned before but my rpms are much more stable now..... but it still does the dead battery thing after it warms up.... any ideas there....?

DIGGLER

iTrader: (1)

one other thing i would do is verify the balancer/timing mark is dead on "0" at top dead center. after that, set it up for around 36-38 degrees total. it may depend on the dizzy for how much you will have initial.

buell_13

that's a bit much isn't it? my timing bracket doesn't even read that high..... but I set it to 0 degrees and advanced it from there till the throttle response was sharp and the rpms were around 750-800.... so do I need to advance it more? Won't that cause detonation issues?

Apeiron

He's talking about centrifugal advance at speed, not base timing at idle.

1986_T/A

General rule of thumb is...run as much timing as you can without knock.

buell_13

So I need to add more?

1986_T/A

I had to recently look this up, as I will be using mechanical/vacuum distributor when I rebuild my TA motor. I thought this link gave a pretty good explanation:

http://www.gofastforless.com/ignition/advance.htm

DIGGLER

iTrader: (1)

run as little timing as possible just to the point where the car makes less power.

buell_13

I turned it back to 0 with the vacuum disconnected and turned out to about 15 degrees..... starts great runs harder than before and throttle is super sharp..... now we wait to see the mileage results......everyone has had great advise and I thank all of you for your help..... I still need to find a good little low end cam but for now I believe im golden...... just have to get used to a quiet 383 till I can afford trick flows.....

buell_13

freaken awesome site.... I knew how to time "I thought" This is a great diy site for timing......

1gary

From this point forward treat this like what it is.A smaller version 400.That's what it amounts to with a 400 crank and stock 400 rods.Don't over extend yourself with those stock rods in rpm.Re-read my post on cam choices from my friend Richard.He has pointed out some important points.

1gary

Hey bud.You like what you have and that's cool.But given the yrs in this business,I have my doubts about 400fwhp.It's because of the SCR and the heads just don't ad up that way.Having a senior moment right now,but it seems to me for every .010 it ='s 1/2 point of SCR.That hurts.

I'm telling you the same thing I told Buell.You built a smaller version of a 400 with 400 stock rods and crank.

And I'm telling you at the sametime I am a huge promoter of torque being king on the street where Hp is well over rated for street light racing.

InfernalVortex

iTrader: (4)

This is a good idea.

Dont worry about cams and heads right now. Likely neither are ideal, but baby steps. Take care of the carb and distributor... work your way down the engine. When you get to the point you're wanting to swap rods and cam, just build a new shortblock.

You need to invest in good heads/intake/carb etc to put a good motor under to begin with. And when you build a new shortblock 3-10 years from now, you can get the rod/stroke ratios just right, get the deck clearance just right, pick a great roller cam for your calculated static compression ratio and get a decent dynamic compression ratio and have a hell of a street screamer.

Starting from the bottom and working up is a good idea if you've already got a different running engine in the car, and you're building it out in your workshop. But you've already got THIS engine in the car. Work your way down it so you can enjoy it in the mean time and when you eventually get to new roller shortblock time, you'll be able to just bolt all the nice parts you already invested in right onto it. .

I agree, my setup with its small cam and vortec heads and everything I've done to it only makes around 290-310 fwhp, but its so torquey that most people would assume it must be making a lot more than that. With 383-400 cubes and small runner heads and so on, it would only exagerrate that relaly strong low end torque curve and that goes a LONG way towards that feeling of power and speed. Ive been in a huge cammed, iron headed 12 second 305 and while it was fast, my car felt faster back when it was doing 14s before I had it dialed in. Manual trans torquey 355 compared to a high strung high RPM 305 with a super loose converter... the car thats more fun on the street is fairly obvious there.

1gary

Ya know,if I was in his shoes,I would get this build running haft decent without getting too involved and the next build would be,no question about it,a LS engine.And after that,there would never be any looking back at the first gen SBC's.

Here is a link where SBC guru David Vizard speaks about stroker strategies and long rod use:
http://www.enginebuildermag.com/Arti...orsepower.aspx

1986_T/A

LS engines are awesome no doubt(I have an LS2) but the costs skyrocket really quickly once you start looking for more power than they came with. And, with every upgrade, comes a mandatory $400-500 tune...

1gary

Well that's hot rodding as I know it.Set your goals and sacrifice some other things to save up to get-er-done.This old boy is starting to look for a LS donor.

Savage388

Oh I didnt build it, if i did it would be very different and have better heads with 5.7 inch rods minimum. in fact if i can get a cheap daily its getting afr 195's this winter. I also wont really argue about the 400 fwhp, its just from my butt dyno lol, but i really think it makes more than 320 thats pretty mild even for a 350.

1gary

Buell.Said better than I can,but what I mean.Cams:

http://www.enginebuildermag.com/Arti..._overview.aspx

1gary

I find it really odd that no one said anything at all with the shorter rod crankshaft counter weight to piston shirt clearance issues.And then re-balancing issues.

1986_T/A

I find it really odd that we went through this entire thread without somebody questioning the obvious. The stock carb/distributor.

1gary

Two shay!!.

DIGGLER

iTrader: (1)

i know of some sbf race engines that had worse rod to stroke ratios than what we are talking about here. they worked, but it was hard on piston skirts and cylinder walls. with a short deck height, ya gotta do what ya gotta do.
im thinking the rod length in op's engine is adequate for what he's going to be doing with it. this thing will probably make peak power by 4500. with a good low end cam and the right carb/dizzy, it should make good low end torque and drive good. and economy should be decent if the carb is right.

1gary

Pick and pull site for ones in his area for the carb:

www.car-part.com

Remember you want a 70's 400 carb and when you go to take it off,tag the vac lines you cut because it is likely your not going to use all the vac ports.

buell_13

I changed the distributor yesterday, runs much smoother.... the carb is unplugged so until I find a non computer controlled quad jet I think I've accomplished a lot with just the distributor. I'm looking at ordering a cam from summit, with a watching intake.... specs are .260/.260 duration .427/.427" lift.... comments say it builds strong low end torque. The intake is shorter than the performer rpm I have so it should compliment the cam rather well.... what are your opinions.... read your cam post Gary that's what lead me to this decision......

1gary

Before you change any cams.Take the time to I.D. what you have..............

buell_13

How would you accomplish that without removing it?

1gary

Well-how do you think it should be done??. Hint- a degree wheel and dial indicator.Research this Buell and tell us a how-to.

buell_13

That's funny..... My point is that to get the correct measurements I have pull the cam.... other wise the best I might could find out is the lift...... Secondly I do not have accesses to all the specific tools needed to find the specs. Bottom line I can get a new cam with bearings and lifters for 85 bucks and I know what it is..... There won't be any error that way due to faulty equipment or me just making a mistake, it's too inexpensive not to just replace it rather than to first find someone with all those tools to measure it with then pull it anyway to get a correct reading.....

haisud

Why people want loud cars? Its disturbing neighbours and your ears. I like quiet and smooth v8 sounds.

1gary

Hint,hint.Measure off the lifter,orrrrrrr.Ant nothing getting pulled there.

Are you sure you don't want fresh lifters too??. Is your current springs going to work with a swap??.

Cars come and go,but tools should be useful no matter which car.

buell_13

I gave the specs of the cam, it should be fine. New lifters come with the cam.... and as I stated I don't have those tools or anyone to barrow them from. I don't intend to sound like I'm ignoring your advise, but if you're not giving advise on the questions I ask I won't continue to ask....

I haven't ordered the cam, but it says it will get great economy as well as the low end, my car has 40xxx miles all original less than four thousand on motor and trans. I just need a little tweaking to get this dialed in, if I have to do it alone I will. Everyone has been great up until this point.... I don't want to waste money on tools I don't use everyday. So if you can tell me a way to measure it without wasting my intake gaskets I'm all ears.... I don't want the intake I have.... the only reason it's on the car is cause I broke a bolt in the stock one and couldn't get it out.... this is an opportunity to put a cam that I know the specs to in and the intake I want..... that's how I'm looking at this, I would like your opinion on this..... the next thing I'm going to do is find another block and build it with 6" rods and two valve flat pistons get a nice set of trick flows.... but right now I can't do that..... I need straight forward cheaper answers....

DIGGLER

iTrader: (1)

one way to get your cam specs would be with a degree wheel and a dial indicator, as suggested above. pull a valvecover, and swap a pair of "checking springs" in place of the valvesprings. these will allow the cam to push the valves open as normal, but won't depress the plungers in the lifters. next you can put a dial indicator on the pushrod cup of the rocker if you have stamped rockers. turning the motor over by hand, you can watch the degrees on the wheel as the pushrod lifts .050" or whatever you are looking for. you can find your duration at .050", max lift, and whatever else your need to know. but, you'll need the tools.

or, you could swap cams since its so cheap. since you are wanting to change the intake as well, you could do them both like you said and that would be a pretty good idea. scan ebay and see if you could locate a good quadrajet for it. something off of a 400, or maybe a 60's/early 70's 350. fuel inlet may be different, though. you can rebuild a quadrajet pretty cheaply with new gaskets and stuff.

1gary

I have had some pretty tough teachers in my past that showed me what I knew how to do on my own.Research.The net is a wealth of info on how to's.That is my point.Also the easiest answer is sometimes neither the best one or the cheapest. How would you feel if you found out later the cam you have now is better??. Spent the money and time for nothing. You do know it was just dumb luck the 350 pistons didn't interfere with the crankshaft counterweights. Those kind of mistakes can and will bite you in the butt sooner than later.

So me being the good internet bud I am,I'm trying to get you started on finding your way. Become the expert and start with experience to post your own how-to's.

Don't get ticked at me for sort of pushing you into that direction. It is totally in your best interests at heart.

BTW-my point about the tools,is you might find you already have a better cam not needing to be replaced and could spend the money on tools you will need to build the next one. What I am suggesting are the basic's in tools for engine building.

1gary

Cam spec terms:

http://www.lunatipower.com/Tech/Cams/CamSpecTerms.aspx

Just another piece of the puzzle of what to measure. These are easy finds on net searches. You need to know about this for the next build. I would think given you pistons be down in the hole,you got a 0 interference engine where you could play games advancing or retarding the cam to change alittle the curve. Doing that is a cheap mod. But you need the cam spec's and need to mock up the change to check clearances. That is done with crank key that are either advanced or retarded. Typical degree amounts is 2 or 4 degrees. You can compound the natural element of a stroker engine by doing this lowering the torque curve. Look at the bottom of the link to see the effects of changing the cam timing events.

buell_13

I didn't get mad, I somehow lost my subscription to this thread..... um the cam is all wrong for the task at hand..... we know this much for sure.... and once I can afford heads then I could spec the cam I have and maybe be able to use it..... but probably just going to throw a thumper in it at that point..... also about the pistons being unbalanced.... would you elaborate on that?

1gary

If you had piston interference with the crank counter wts,you would have to cut the crank counter wts and resulting re-balance. Either way it should have been balanced.

Buell. We're at 190 posts on this thread where everyone involved has spent alot of time and effort. When you say your just going to throw a Thumper cam in it,it is the same thing as saying your still not willing to learn to learn about hot rodding or engine building. Those cams are mind games that sound like but are not. Just swap the dizzy and carb and drive it. I don't see any useful reason to continue to pursue this thread as long as you don't want to change. You just want the quick and easy answers and for you there are none.

buell_13

Hey bud read the post I changed the distributor and am currently looking for a decent carb, I listened to you..... I've listened to everyone even inferno.... I think diggler is right the cam isn't right with my intake...... I want to put the right intake on..... but I need to work on the mechanical timing on the distributor first I think..... I was asking you more about the balance stuff because I matched the pistons to the same cylinder and the rods are matched from the 400 so I thought if the rods are balanced and the pistons put back where they were it would be right..... if not what would the symptoms be? I'm not ignoring anyone most of all you.... you are very knowledgeable and I am very glad to see you chime in. I have not purchased the cam yet because you haven't said it's a good idea.... I just figured as cheap as it is why not? But right now I have put 100 miles on the car since changing the distributor and I still have over a half tank.... so my mileage has at least doubled..... should be around 20 mpg. It's awesome and that's thanks to a post here.... I'm very grateful please understand that.... I have thought about getting a demon carb but I know how temperamental they can be..... so I'm still looking for a non cc quadrajet. I'll say this if I can get this cam figured out.... what specs should it be to keep it?

buell_13

Oh about the thumper cam, I meant after I buy heads and put this motor together right.

1gary

Gezzz- to get to the core of the info is like peeling a onion with you. Look,key question for you to ask yourself is the 5.7 rods the same wt as the 5.6 rods and is the 350 stroke crank balanced the same as the stroker crank??. This is just another example of a long,long,list of "it's good enough" build tactics. Your bearings dependent on how far out of balance you are,are not going to show you back all the love. I have to assume before you bought a stroker crank you started with a .040 over 350??. Or you started with a .040 over 400. I still don't get where you had a choice between the 5.7 or the 5.6 rods and had both on hand. And I am almost afraid to ask.

It's because of the attitude of "it's good enough" build tactics that I am telling you to find a carb replacement and drive it as is. No other further plans to build anything else. Just end it all. It take thousands to build a 383,not hundreds. and I am saying all this as the best advise after all the posts we have exchanged and having gotten to know you some. Now as I am again chewing on another pair of tums.LOL.

SLEEPER 86

A Qjet with mechanical secondaries? As far as I know there aint no such animal. If your Qjet was set up for your 305 stock, it's probably lean in all the circuits for your 383. I've been a holley guy all my life but the Qjet is a fine carb when properly set up. Best to go find the old Qjet expert in your area and get it set up properly. Easy if you know how, if you don't, you can mess things up completely!

mmadden55

Trick flow or Patriot aluminum heads.

1gary

The Patriot brand name is junk parts.